Several proposals have been made for child-proofing of electric plugs, and as shown in U.S. Pat. No. 3,763,457 and U.S. Pat. No. 4,391,481, guards have been proposed which extend around the prongs of an electrical plug. These guards can be collapsed while the plug is inserted into a wall outlet. Such collapsible guards are resiliently flexible, and upon withdrawal of the plug from the wall outlet, the guard can return to its initial shape. In this way, the guard protects against inadvertent contact with the prongs of the plug while inserting or withdrawing from the wall outlet. Additionally, guards have been proposed as described in U.S. Pat. No. 4,060,297 which prevent use of electric plug, and removal of the guard is made difficult in order to protect against inadvertent use of the plug by a child.
In order to provide more complete safety in a household with small children, it is necessary that a safety device for an electrical plug not only shield against inadvertent contact with the electrical prongs during insertion or removal of the plug from a wall outlet, but also prevent unauthorized use of the plug by a small child. Therefore, an object of the present invention is to provide an inexpensive safety shield for an electric plug which will not only guard against inadvertent contact of the electrical prongs during insertion or removal from a wall outlet, but will also disable the plug to prevent small children from even attempting to insert the electric plug into a wall outlet.